Adducts of Piperidine, Piperazine, Methylpiperazine, and Morpholine with Bis(β-Ketoenolates) of Nickel(II)

1972 ◽  
Vol 50 (16) ◽  
pp. 2557-2560 ◽  
Author(s):  
G. Marcotrigiano ◽  
R. Battistuzzi ◽  
G. C. Pellacani

The bis(β-ketoenolates)nickel(II) adducts of piperidine, piperazine, methylpiperazine, and morpholine are isolated in the solid state and investigated by magnetic measurements and electronic and i.r. spectra. Magnetic measurements and electronic spectra give evidence of trans-octahedral configuration while i.r. spectra show that the amines are coordinated to the nickel atom towards the nitrogen atom. The new band found in the range 385–300 cm−1 for all complexes can be assigned to Ni—N vibration. In the Ni(DBM)2•4B (B = methylpiperazine and morpholine) the two additional bases are not coordinated to the metal atom.

2018 ◽  
Vol 73 (11) ◽  
pp. 793-801
Author(s):  
Aleksej Jochim ◽  
Christian Näther

AbstractReaction of Mn(NCS)2with pyrazole leads to the formation of three compounds with the compositions Mn(NCS)2(pyrazole)4(1), [Mn(NCS)2]2(pyrazole)6(2) and Mn(NCS)2(pyrazole)2(3). Compound1, already reported in the literature, consists of discrete complexes, in which the Mn(II) cations are octahedrally coordinated by four pyrazole ligands and two terminally N-bonded thiocyanate anions. In compound2each of the two Mn(II) cations are coordinated octahedrally by three pyrazole ligands and one terminal as well as two bridging thiocyanate anions, which link the metal cations into dimers. In compound3also octahedrally coordinated Mn(II) cations are present but they are linked into chainsviacentrosymmetric pairs ofμ-1,3-bridging thiocyanate anions. Upon heating compound1loses the pyrazole co-ligands stepwise and is transformed into the chain compound3viathe dimer2that is formed as an intermediate. Magnetic measurements on compounds2and3reveal dominating antiferromagnetic interactions, as already observed for 1D Mn(NCS)2coordination compounds with pyridine based co-ligands.


2002 ◽  
Vol 67 (12) ◽  
pp. 825-832 ◽  
Author(s):  
Raghu Prasad ◽  
Mala Mathur

Metal complexes of a 20-membered tetraazamacrocycle 2,12-dimethyl-3,13-di-n-propyl 1,4,11,14-tetraazacycloeicosa-1,3,11,13-tetraene(L) of the type [MLX2]X(M=Cr(III), Fe(III); X=NO3)[CoLNO3]NO3, [NiL(NO3)2], [CuL]Cl2 and [ZnLCl2]have been prepared by 2+2 cyclocondensation of 2,3-hexanedione with 1,6-diaminohexane in the presence of metal ions as templates. These complexes were characterized by elemental analyses, conductances, IR and electronic spectra and magnetic measurements.


2004 ◽  
Vol 1 (1) ◽  
pp. 110-115
Author(s):  
Baghdad Science Journal

We found that 4,5- diphenyl- 3(2- propynyl) thio- 1??-triazole [1? forms a complex with Pd (11) ion of ratio 1:1 which absorbs light in CH2CI2 at 400 nm, and 4,5- diphenyl- 3(2- propenyl) thio- 1,2,4- triazole [II] forms complexes with Pd (II) ion of ratio 1:1 which absorbs light at 390 nm, and of ratio 2:1 which absorbs light at 435 nm. On the other hand, we found that the new derivative 4- phenyl- 5( p- amino phenyl) -3- mercapto- 1,2,4- triazole ?111? forms complexes with Cu (II) ion of the ratio 1:1 which absorbs light at 380 nm, with Ni (II) ion of the ratio 3:1 which absorbs light at 358 nm; and with Co (11) ion of the ratio 3.2:1 which absorbs light at 588 nm. The ratio of the complexes were determined by measuring the electronic spectra of the complexes in CH2G2 and (CH^NCHO at different concentrations ofthe ligands and f?xed ' •' of the metal ion in every case, then applying the molar ratio plots on the data. Our results were confirmed by precipitating most ofthe above complexes in solid state, and then each complex was analyzed elementally.


2004 ◽  
Vol 814 ◽  
Author(s):  
H. Detert ◽  
O. Sadovski ◽  
Erli Sugiono

AbstractThe fourfold Horner olefination of tetraphenylmethane or –silane with fourp-methyl- phosphonate groups and a variety of aromatic aldehydes with donor groups or extended conjugated systems results in the formation of tetrahedra from four chromophores connected via a central atom. Electronic spectra in solution reveal an electronic interaction between the π-systems. In the solid state, the emission of compounds with a dense packing is nearly identical to the solution spectra, more open structures show significant red shifts. The emission of scaffolds with 1-styrylpyrene chromophores is nearly completely quenched. Most of these tetrahedra are thermally stable up to 420°C. Depending on the diameter of the scaffold, glass transitions occur between 99°C and 169°C.


Author(s):  
A.V. Yatsenko ◽  
K.A. Paseshnichenko ◽  
S.I. Popov

The crystal and molecular structures of 2-methyl-1-methylamino-anthraquinone (I) and 1-methylphenylamino-anthraquinone (II) were studied by the X-ray single-crystal diffraction and the visible spectra of crystalline specimens and their solutions were recorded. The molecule I is closely planar, whereas in the molecule II the amino group is 58° rotated out of the plane of the anthraquinone skeleton. In both structures the molecules pack in stacks. The comparison of experimental and calculated (on the DFT and AM1 levels) molecular structures, together with the comparison of experimental and INDO/S-calculated electronic spectra, give the evidence that molecular conformations (especially for II) change upon transfer from the solid state to solutions, and the π-delocalisation throughout the whole molecule enhances in the solid state.


1993 ◽  
Vol 48 (9) ◽  
pp. 1181-1186 ◽  
Author(s):  
H.-D. Hausen ◽  
Wolfgang Kaim ◽  
Andreas Schulz ◽  
Michael Moscherosch ◽  
Jeanne Jordanov

Crystal and molecular structure analysis of 1,4-diethylquinoxalinium iodide shows a virtually planar quinoxaline ring with 11 conjugated π-electrons. In contrast to the triiodide of the 1,4,6,7-tetramethyl derivative or to the tetraphenylborate salt of 1,4-diethylquinoxalinium cation radical the iodide exhibits π-π-dimerized radical cations in the solid state with synplanar ethyl groups and a rather small intermolecular distance of about 315 pm between the π-planes of the primarily interacting 1,4-diazine rings. Solid state magnetic measurements between 2 and 300 K show considerably diminished magnetic moments due to partial spin-pairing, and UV/VIS spectroscopic measurements in acetonitrile reflect the π—π-interaction in solution through the appearance of a long-wavelength absorption band.


2011 ◽  
Vol 7 ◽  
pp. 119-126 ◽  
Author(s):  
Heiko Ihmels ◽  
Jia Luo

Dibenzobarrelene derivatives, that are annelated with a pyrrolinium unit [N,N-dialkyl-3,4-(9',10'-dihydro-9',10'-anthraceno-3-pyrrolinium) derivatives], undergo a photo-induced di-π-methane rearrangement upon triplet sensitization to give the corresponding cationic dibenzosemibullvalene derivatives [N,N-dialkyl-3,4-{8c,8e-(4b,8b-dihydrodibenzo[a,f]cyclopropa[cd]pentaleno)}pyrrolidinium derivatives]. Whereas the covalent attachment of a benzophenone functionality to the pyrrolinium nitrogen atom did not result in an internal triplet sensitization, the introduction of a benzophenone unit as part of the counter ion enables the di-π-methane rearrangement of the dibenzobarrelene derivative in the solid-state. Preliminary experiments indicate that a cationic pyrrolidinium-annelated dibenzosemibullvalene may act as phase-transfer catalyst in alkylation reactions.


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